1. Field of the Invention
The present invention relates to a camera system having a multi-pattern light measuring apparatus in which brightness or luminance of an object is calculated based on the luminance information from a plurality of divided regions of the photographing image plane.
2. Description of the Related Art
Conventionally, there has been provided a various camera systems having the multi-pattern light measuring apparatus in which the photographing image plane is divided in a plurality of light measuring regions so that the luminance of the object ar calculated based on the luminance information from the respective regions.
One of these conventional camera system is provided with a light measuring apparatus in which the focus detections of some focus detecting regions in the photographing image plane are effected and a spot light measuring of a light measuring region including one of the focus detecting regions which is selected based on the focus detections is performed so that the luminance of the object is calculated based on the measured light values of the light measuring region including the selected focus detecting region (See U.S. Pat. No. 4,423,936). More specifically, according to the above camera system, considering such a fact that a main object intended to be photographed is normally located at a place closest to the camera, one focus detecting region where the closest object is located is chosen from some focus detecting regions and the luminance of the object is calculated based on the measured light value of the light measuring region including the selected focus detecting region. Thereby, the accurate luminance of the main object which is mainly to be photographed can be advantageously obtained without the necessity of the AE lock operation, resulting in an easy operation of camera.
Incidentally, in the above-described camera system having a plurality of focus detecting regions, in some cases a focus detection in connection with a wide area including many regions is desired, while in the other cases a focus detection in connection with a narrow specific area including less regions is required.
If, another object is present between the camera and the main object which one intends to photograph, the accurate luminance of the main object can not be obtained in the above conventional camera system because the luminance of the object closest to the camera is calculated. In order to eliminate the above disadvantage, it is preferable to narrow the focus detecting area to detect only the focusing condition of the regions which do not include said another object.
Conventionally, however, there has been provided no camera system which comprises a light measuring apparatus, in which the luminance of the object is calculated based on the measured light values of the light measuring regions corresponding to the focus detecting regions where the main object is located, and means for altering the focus detecting area.